Content:
1. A general introduction about fjords
3. A short description of the main fjord regions
3c. North American fjords in British Columbia and Alaska
3d. Fjords of the North Atlantic: Norway, Scottia, Greenland, Iceland, Spitsbergen
1. A general introduction about fjords
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Considering the coastline covered by fjordlands and the ecological and economical importance this type of coast represents, fjord research is dramatically under-represented in marine science. This has logistic, technical-historical, political and in some cases even cultural reasons. The morphology of fjordlands and the climatic situation were generally unfavourable for development and, with some exceptions in the North Atlantic, Universities are hardly found close to fjords. Access still depends to a large extend on boat traffic, distances are large and the weather conditions are often harsh. At the end of 19th and the beginning of the 20th century when marine research had an important boom, sampling was done either in the intertidal or from boats. The steep intertidal in fjords often characterized by smooth rock is hard to access and due to the frequent presence of a low salinity layer often exhibits a comparably poor intertidal life which seems not to reward for the long boat trips to access it. The traditional gear on boats, grab samplers and dredge nets do not work very well on hard substratum and where soft sediment is found in fjords it is often comparably poor in species. As a consequence fjord regions have been of lower interest for the developing marine science community and marine stations have been built in regions that seemed to be more favourable. As a result, marine science has evolved largely excluding fjord regions. With the development of new techniques marine environments that have been out of reach for a long time could be explored. But deep sea environments and polar regions seemed far more exciting than closer coastal environments - fjord regions dropped out of the search pattern again. With growing economic interest in fjord regions through fisheries, logging, aquaculture and tourism, the demand for scientific data is rising and the lack of biological knowledge of these environments becomes obvious. Techniques like SCUBA diving and remote operating vehicles (ROV) allow exploring the subtidal rocky slopes and reveal astonishing diverse and unique ecosystems. Fjord regions seem to be high latitude biodiversity hot spots and offer the possibility to address biological questions of global importance. But the comparably low number of researchers in the different fjord regions often still work very isolated and the topics are very locally restricted. |
3. A short descriptions of the main fjord regions
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3a. The Chilean Fjord region
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(text and two pictures from the Fiordland research page of the University of Otago)
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3c. North American fjords in British Columbia and Alaska
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3d. Fjords of
the North Atlantic: Norway, Scottia, Greenland, Iceland, Spitsbergen
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(Crepidula sp.) Although no quantitative data are available yet the
current studies indicate very high overall species diversities in the
subtidal communities below the influence of the Low Salinity Layer where
the distribution is mainly patchy. The
high diversity is often accompanied by high biomass – an elsewhere
rarely observed combination. Eurybathy, the presence of deep water
organisms in shallow water, is a very abundant phenomenon but many of the
explanations given for this phenomenon in other regions do not fit for the
Chilean fjords. Most spectacular and eye-catching representatives of this
phenomenon are the only recently discovered large banks of deep water
corals that can regularly be found in depths as shallow as 20 m, far above
the end of the euphotic zone. They are mainly built up by the solitary or
pseudo ramified Desmophyllum dianthus and two minor species Caryophyllia
sp. and Tethocyathus sp. Although there are some differences in
structure and ecology these coral banks are comparably to the Lophelia
reefs in Norwegian fjords, at least in extension. Very special bacteria
communities can be found close to underwater thermal springs that are
manifestations of the volcanic activity in this region.
The
geomorphology and hydrography of Doubtful Sound have a significant
influence on the distribution and abundance of organisms within the
fiord. The thinning of the low salinity layer (LSL) with distance
along the fiord results in strong horizontal gradients in primary
productivity and diversity . Recruitment processes and larval
transport processes are also strongly influence by the hydrographic
processes within the fiord. The LSL also dictates that many of the
intertidal and shallow subtidal organisms are euryhaline (eg. Ulva
lactuca, Patiriella regularis). In addition, the layer controls the
vertical distribution and zonation patterns or marine organisms
within the fiord, both directly and indirectly. This is especially
true for key species such as the predatory starfish and the grazing
sea urchins.
At the top of Fiordland's food
web are bottlenose dolphins. A
resident group in Doubtful Sound has been the subject of a decade of
study - chiefly focussed on how the dolphins use the habitat, and
quantifying social relationships. These studies now extent to the
other fiords, and to detailed studies of acoustic behaviour and
impact of dolphin watching.
